Portosystemic venous shunt in the patients with Fontan circulation

Portosystemic venous shunt (PSVS) is a vascular anomaly between the portal and systemic veins, resulting in several critical complications. Although PSVS is often associated with congenital heart diseases, the clinical association between Fontan circulation and PSVS has not been elucidated. This study aimed to investigate the clinical features of Fontan patients with PSVS. Two hundred thirteen patients who underwent Fontan procedure are being followed up at Adult Congenital Heart Disease clinic in Kyushu University Hospital. Among them, 139 adult patients underwent cardiac catheterization between January 1, 2011 and September 30, 2019. Medical records were reviewed to investigate the laboratory, echocardiography, and cardiac catheterization findings, as well as clinical manifestations and outcomes. Eleven Fontan patients received the diagnosis of PSVS. The median age at cardiac catheterization was 25 (range 18-45) years. Fontan operation was performed using extracardiac conduit or lateral tunnel 22 (16-35) years previously. Ten patients presented with chronic heart failure [New York Heart Association class 2 (n = 5) and 3 (n = 5)]. The median level of peripheral oxygen saturation was 87 (70-95)%. Cardiac catheterization showed increased cardiac index [5.3 (2.72-14.3) L/min/m²] with or without high central venous pressure [18 (9-25) mmHg]. Although the pulmonary vascular resistance was within the normal range, the systemic vascular resistance was decreased [7.08 (1.74-18.6) Wood units]. Fontan patients complicated with PSVS had increased cardiac output. The presence of PSVS in Fontan circulation might be associated with unfavorable long-term outcome.